In a previous post, I discussed what I love about using Khan Academy in my grade 6 classroom. In this post, I will discuss some of the problems I have encountered and what I’m doing to work around them.
Students have a hard time selecting exercises that are appropriately challenging and relevant to the unit of study.
While I do love being able to let students work at their own pace in order to foster mastery and a sense of success among all students, it is a bit of a juggling act to make sure that all students are using their time efficiently. There are definitely those students who are very motivated by the incentives and will practice easy exercises over and over again just to add to their store of points. Other students find it amusing to look for the most advanced topics that they can find and see how many questions they can answer correctly by merely guessing (I would love to turn that one into a word problem about probability, but that’s a whole other discussion). And, of course, there are the students who are overwhelmed with the options (over 300 different exercises) and don’t know where to start.
To get around this, I am quite intentional about developing and maintaining specific habits amongst my students in how they use Khan Academy when they are under my supervision. In general, I will assign specific topics that students must practice. Sometimes these are assigned for homework and sometimes I have them working in-class so that I can work with students who need help. In other cases, I will suggest a number of topics, and students are free to choose from amongst those topics. I generally also post a list of suggested topics for students who need an additional challenge. Regardless of what has been assigned, students know that they must work on the assigned topics before they are allowed to work mastery challenges or topics of their own choosing. At the beginning of class, we work together to make a ‘to-do’ list with a specific sequence, so that the highest-priority items are completed first.
The latest version of the coach’s dashboard on Khan Academy supports this quite nicely, as it allows me to view student progress on the skills that I have specifically chosen. Of course, basic classroom management also comes in to play: it’s essential to circulate to keep an eye on what’s happening in the room.
Students master a lot of skills but struggle apply those skills in real world situations.
While there are many great, great things about Khan Academy, it is not a complete math program. The quality of the exercises is improving all the time and I am always pleased to see when the exercises include word problems; however, the structure of the site results in a significant and inevitable flaw: because exercises are always organized by topic, students are essentially told what skill to use to solve each problem, rather than having to select an appropriate math skill to use in a real-world context. The Mastery Challenges help to circumvent this limitation as the questions are drawn from a variety of different topics, but the topics that are included in the Mastery Challenges are generally the topics that have been practised recently, so students are recognizing and repeating what they’ve already done, rather than making connections between the range of skills that they have and the particular problem that they are trying to solve.
This is why Khan Academy can only be one part of a broader math program. It is a great tool for helping students build math skills, but they must be given opportunities to apply these skills in real-life situations. Inspired by Dan Meyer’s Ted Talk, I have made a specific effort in my teaching to make sure that students get to grapple with messy, real-world problems that require a variety of the skills that they have developed over the course of the year. One of my favourites is the “Big Problem” that I wrote about in a previous post, but I use smaller, more traditional problem-sets in every unit as well.
Proficient students quickly develop a sense of mastery in the exercises but struggle to develop a similarly well-developed ability to communicate their reasoning.
I recently dealt with a few tearful students who, having amassed thousands of points and mastered dozens of topics on Khan Academy , were disappointed with their grades on an assessment task that required them to solve a series of problems and show their work clearly. When submitting answers on Khan Academy, students are only required to enter an answer; there is no requirement for students to show how they got that answer. While this is totally fine when the goal is for students to develop specific skills, students need opportunities to communicate their reasoning.
This is another reason that I think it is so important for students to work on word problems – especially the complicated real-world problems. The practice of communicating their steps not only helps students learn how to break a big problem into smaller steps, it also gives them experience with what real mathematicians do: namely, finding an answer to a question and telling other people how they got it and why it’s valid.
At the end of the day…
I will continue to use Khan Academy in my classroom, but always as a reflective and responsive practitioner. I don’t think any math program will be perfect, nor do I think that there’s a math program that will meet all the needs of every student every year. So, I’ll keep doing what works well and change what doesn’t work… that’s my problem-based learning!